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dc.contributor.advisor Marsaglia, Kathleen en
dc.contributor.author James, Dawn E. en
dc.date.accessioned 2016-03-29T18:27:40Z en
dc.date.available 2016-03-29T18:27:40Z en
dc.date.copyright 2003 en
dc.date.issued 2003-12 en
dc.identifier.uri http://hdl.handle.net/10211.3/164487 en
dc.description Includes bibliographical references (leaves 34-40) en
dc.description California State University, Northridge. Department of Geological Sciences. en
dc.description.abstract The Waipaoa River System (WRS) is located on the eastern margin of North Island, New Zealand (NINZ). This region is an actively deforming and eroding forearc where sedimentary successions are being recycled into younger deposits. The WRS has developed on uplifted Mesozoic and Cenozoic forearc basin sequences. Since the Pliocene, there has been periodic input of volcanic ash into the forearc from the Taupo magmatic arc, which is located to the west of the drainage. The size and lithology of bedload clasts were recorded at five sites (n= lOO per site) along the Waipaoa River. The gravel clasts are predominately mudstone/siltstone with lesser amounts of sandstone, claystone, and limestone. The proportion of calcareous clasts increases from 16% to 4 7% at 65 km downstream; this increase is possibly due to calcareous sediment input from tributary streams. Sand samples were collected from exposed sandy bars along the length of the Waipaoa River, along several tributary streams to the Waipaoa River, and down the length of the Waimata River. Stained thin sections prepared from these samples were point-counted using the Gazzi-Dickinson method, with a total of 400 points per thin section. The petrographic analysis of 15 bulk sand samples shows them to be composed predominantly of sedimentary lithic fragments (average QFL%L = 86%; LmLvLs%Ls = 94%) with lesser quartz (average QFL%Q= 11 %) and feldspar (average QFL%F= 3%) and relatively minor volcanic lithic (LmLvLs%Lv = 2%), carbonate/limestone (4% average of total grains) and other components (2% average of total grains) such as mica, glauconite and dense minerals. Petrographic analysis of 5 sand subfractions (very fine to very coarse) for 14 samples, indicate that there is a distinct relationship between grain size and sand composition. Quartz and to a lesser degree feldspar grains are sequestered in the finer fractions, with QFL% Q up to 53% and QFL%F up to 9% in the very fine fraction. The sand data and clast count data show that the Waipaoa River sediments are dominated by the crushed and sheared sedimentary rocks of the East Coast Allochthon located in the upper portion of the catchment. Despite the proximity of the Waipaoa River to an active volcanic arc (- 250 km), its sediment load contains a relatively small proportion of volcanic debris. There is also a relatively distinct compositional difference between the Waipaoa and Waimata rivers, where the proportions of volcanic lithic fragments vary, as do the percentages of specific mudstone lithic fragment types. The Waipaoa River is dominated by non-calcareous mudstone lithic fragments while the Waimata River is dominated by calcareous mudstone lithic fragments. These compositional differences suggest that in older alluvium and offshore sedimentary sections it may be possible to distinguish sand derived from purely a Miocene/Pliocene source from that derived from the upper catchment of the Waipaoa River. en
dc.description.statementofresponsibility by Dawn E. James en
dc.format application/pdf en
dc.format.extent vii, 105 pages en
dc.language.iso en en
dc.publisher California State University, Northridge en
dc.rights.uri http://scholarworks.csun.edu//handle/10211.2/286 en
dc.subject.other Dissertations, Academic -- CSUN -- Geology. en
dc.title Sand provenance in the Waipaoa River System, North Island, New Zealand en
dc.type Thesis en
dc.date.updated 2016-03-29T18:27:40Z en
dc.contributor.department Geological Sciences en
dc.description.degree M.S. en
dc.contributor.committeemember Sloan, Jon en
dc.contributor.committeemember Gomez, Basil en
dc.contributor.committeeMember Sloan, Jon en
dc.contributor.committeeMember Gomez, Basil en
dc.rights.license By signing and submitting this license, you the author grant permission to California State University, Northridge Graduate Studies to submit your thesis or dissertation, and any additional associated files you provide, to CSUN Scholarworks, the institutional repository of the California State University, Northridge, on your behalf.You grant to CSUN Scholarworks the non-exclusive right to reproduce and/or distribute your submission worldwide in electronic or any medium for non-commercial, academic purposes. You agree that CSUN Scholarworks may, without changing the content, translate the submission to any medium or format, as well as keep more than one copy, for the purposes of security, backup and preservation. You represent that the submission is your original work, and that you have the right to grant the rights contained in this license. You also represent that your submission does not, to the best of your knowledge, infringe upon anyone's copyright. If the submission contains material for which you do not hold copyright, or for which the intended use is not permitted, or which does not reasonably fall under the guidelines of fair use, you represent that you have obtained the unrestricted permission of the copyright owner to grant CSUN Scholarworks the rights required by this license, and that such third-party owned material is clearly identified and acknowledged within the text or content of the submission. If the submission is based upon work that has been sponsored or supported by an agency or organization other than the California State University, Northridge, you represent that you have fulfilled any right of review or other obligations required by such contract or agreement. CSUN Scholarworks will clearly identify your name(s) as the author(s) or owner(s) of the submission, and will not make any alterations, other than those allowed by this license, to your submission. en


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